Electric switch operating apparatus



May 3, 1938. c, HI L ET AL 2,116,396

ELECTRIC SWITCH OPERATING APPARATUS Filed May 22, 1934 2 Sheets-Sheet l4! 44 29 Figs.

2&

l nventors:

Charles H. l-HIL.

Arvid E. Armier'som Then Attorneyy 3, 1938. c. H. HILL ET AL 2,116,396

ELECTRIC SWITCH OPERATING APPARATUS Filed May 22, 1934 2 Sheets-Sheet 2II'NEYTC'OI'SI Charles H. Hill, Ar'vicl E. Anderson,

Wei] AttorneQ.

Patented May 3, 1938 PATENT OFFICE ELECTRIC SWITCH OPERATING APPARATUSCharles H. Hill and Arvid E. Anderson, Drexel Hill, Pa., assignors toGeneral Electric Company, a corporation of New York Application May 22,1934, Serial No. 726,887

Claims. (01. 200-89) Our invention relates to electric switches of thattype in which the switch is tripped to open circuit position in responseto an abnormal condition in the circuit controlled thereby and is 5automatically reclosed after being tripped open.

Certain forms of switches of this type heretofore constructed haveemployed a collapsible mechanism connecting the switch with theoperating device therefor by the collapse of which mechanism the switchwould be permitted to open independently of the operating device, theconstruction ofthe mechanism being such that it would subsequently resetitself automatically in readiness for another switch closing operation.

The mechanism also was provided with a circuit controller forreenergizing the operating device when the switch moved to open circuitposition in response to an abnormal condition. In certain forms of suchapparatus the difficulty has arisen that the operating device has beenreenergized before the resetting operation of the mechanism wascompleted with the result that the switch failed to reclose.

. It is one object of our invention to provide an improved switchoperating apparatus which will avoid this difiiculty. Another object ofour invention is the provision of apparatus which will avoid thisdifliculty where the switch is provided with means for causing arepeated reclosing of n the switch at predetermined intervals for apredetermined number of times should the abnormal condition persist.

Our invention will be better understood from the following descriptiontaken in connection 35 with the accompanying drawings, and its scopewill be pointed out in the appended claims.

Referring to the drawings Figs. 1, 2 and 3 illustrate the switch andoperating mechanism therefor in three different positions. Figs. 4, 5and 6 40 show the controlling device of the mechanism drawn to a largerscale and corresponding in position respectively to its positions in thepreceding figures.

We have chosen-to illustrate our invention as 45 actuated by a motordriven centrifugal device which device. it will be understood, is ofsuch a character that it will continue to rotate after the switch hasbeen closed thereby and the motor deenergized because of the inertia ofthe moving 60 parts, until finally it comes to rest by reason of thefriction and windage thereof.

Referring to Figs. 1, 2 and 3, the switch is shown in part only beingrepresented by the fixed contacts I and the cooperating movable contact2. one of the leads I to the fixed contacts being provided with theusual winding 4 which connects with the relay 5 for the operation of theusual switch tripping means. The operating rod 1 of the switch connectswith the lever B which in turn connects through the toggle 9 with the 5collapsible mechanism comprising links H) and l l which links arepivoted together at I2 and are retained in alignment as shown by Figs. 1and 3 by means of the latch i3, this latch being pivoted to link l0 andarranged to be tripped to dis- 10 engage member Ii by the trippingmagnet I which is connected to be controlled by relay 5. Member H at itsfree end is pivoted to the lever,

16 one end of which comprises a counter-weight while the other end ispivotally connected with 15 the centrifugal mechanism comprising theflyballs l1 and connecting linkage l8, the centrifugal mechanism beingrotated by the electric motor IS.

The lever 8 has an arm carrying the movable 20 contact 2| of anauxiliary switch whose rear contacts 22 are in the circuit of thetripping magnet and whose front contacts 23 are in the circuit of relay24 to be described later. At 25 we have shown a fluid reclosing devicevwhose 25 internal construction is illustrated by Figs. 4, 5 and 6 andwhich in the position illustrated by Fig. 3 is adapted to close a.circuit connected with the source of supply 26 through the switch 2|,

23 and the winding of relay 24. The latter relay when energized connectsthe fixed contacts 21 so as to seal in the winding and it also connectsthe fixed contacts 28 so as to close the circuit of motor l9 whichreceives energy from the same source 26. By means of the hand switch 29the relay 24 may be manually actuated and through the hand switch 3|!the tripping magnet l4 may be manually actuated.

As shown in Figs. 4, 5 and 6, the reclosing device 25 comprises a closedreceptacle having a transverse partition therethrough dividing it intothe chambers 32 and 33, the device being partially filled with asuitable conducting liquid such, for example, as mercury. In chamber 33is the receptacle 34 in which are the two conductors 35 and 36, thelatter being insulated except at its upper end whereby the fluidcontained in the device will eiectrically connect the two conductorsonly after the receptacle 3! has been substantially filled. Thepartition across the device is provided with the two tubes 38 and 39forming restricted passages through which the fluid may pass at apredetermined rate. Thus when the device is in the position shown byFig. 6 the fluid in chamber 32 runs through the pipe 38 into thereceptacle 34, and when the device is inverted to the resetting positionshown in Fig. 4 the fluid, after being dumped from receptacle 34,returns to chamber 32 through the other tube 39. The device 25 isdisclosed and claimed in the copending application of Arvid E. Anderson,Serial No. 704,653, filed December 30, 1933, which became Patent No.2,055,327 on September 22, 1936.

The device 25 is pivotally mounted on the transverse axis 40 and isprovided with the arm 4| by which it is partially rotated on that axis.The device is arranged to have its angular position controlled by theposition of the switch operating mechanism. Connection between the arm4| of device 25 and the link l0 includes the link 42, the bellcrank 43,and the rod 44. On one end of bellcrank 43 is pivoted the block 45 whichis arranged to slide on rod 44 and engaging opposite sides of this blockand surrounding the rod 44 are the two coil springs 46 and 41. Spring 46is retainedby the head 48 on the lower end of the rod, and spring 41 isretained by the block 51 slidably mounted on the rod: The latter blockhas the transverse pin 49 therein which engages in a slot in thelatching lever 50. The opposite end of this lever-is arranged to engagea projection on the link 5| pivoted at 52 whose lower end pivotallyconnects with the link 53. Spring 54 serves to resiliently retain link5| against the stop 55. Link 53 is slotted at its opposite end andengaging in this slot is the pin 56 projecting from lever I6.

The operation of the above-described apparatus is as follows. Assumingthe switch and the operating mechanism therefor to be in the closedcircuit position illustrated by Fig. 1, should an abnormal conditionsuch as a short circuit occur on the line controlled by the switch,relay 5 would be operated in response thereto closing the circuit oftripping magnet M to release the latch l3 whereby the collapsibleconnection comprising members lll and I would move to the position shownby Fig. 2 to allow the switch to drop to its open circuit position. Theswitch thus would be tripped free of the centrifugal operatingmechanism. Unless the centrifugal apparatus is rotating at that time thelever I6 by reason of its weight will thereupon move to the positionshown by Fig. 3, in which position the collapsible mechanism comprisingmembers l0 and II will reset itself to its extended or non-collapsedcondition'as shown in Fig. 3, the latch l3 dropping over the end of linkH to the position shown in that figure. The device 25 by reason of itsconnection with the link In now is retained in its upright position asshown'in Fig. 3 in which position the fluid contained therein runsthrough pipe 38 into the receptacle 34 which in a predetermined time,that may be several seconds, becomes filled with the liquid to the pointwhere the terminals 35 and 36 are electrically connected thereby. Thecircuit thus is closed through the device 25, switch 2|, 23 and thewinding of relay 24. The energization of this relay closes the sealingcircuit thereof and also closes the circuit of the motor l9 whereuponthe centrifugal mechanism is started rotating. When this mechanismreaches suflicient speed the lever I6 is rotated in a counterclockwisedirection from the position shown in Fig. 3 to that of Fig. 1, thusmoving the switch to closed circuit position as shown by Fig. 1. Sincedevice 25 now is in its inverted position, the fluid no longer isretained 'by the receptacle 34, hence it no longer connects terminals 35and 36 and since switch 2|, 23 is no longer closed, relay 24 isdeenergized thereby opening the circuit of motor |9..

If the aforementioned abnormal condition on the line controlled by theswitch has been cleared in the meantime, the switch will remain closed.However, should the abnormal condition persist the tripping magnet l4will again be energized to cause the switch again to be tripped to theopen circuit position shown in Fig. 2. Because of the inertia of themotor armature and the fiyballs, the centrifugal device will continue torotate for sometime after the switch has reached its closed position,regardless of whether it remains closed, and the motor has beendeenergized by the release of relay 24 and this continued rotation ofthe centrifugal device will maintain lever IS in the position shown byFig. 2 preventing the resetting of links l0 and II. While these linksare in this collapsed condition, see Fig. 2, the reclosing device 25 isretained in its horizontal or intermediate position by reason of thelatch comprising the lever 50 and the cooperating projection on link 5|.As long as device 25 remains in this intermediate position the fluidtherein does not pass the partition in the device, hence the deviceremains inactive. Receptacle 34 is empty since the device 25 reached theinverted position during the closing operation. When the speed ofrotation of the centrifugal device decreases to the point where it is nolonger able to retain lever 6 in the position shown in Fig. 2 the heavyend of this lever causes the lever to rotate clockwise to the positionshown by Fig. 3 which allows the collapsible links l0 and II to reset.By this movement of lever I6, the pin 56 therein by engaging the end ofthe slot in link 53 moves link 5| against spring 54 and releases thelatch 56, whereupon spring 41 causes the device 25 to rotatecounterclockwise to the position shown by Fig. 3. The fluid in thechamber 32 of this device now begins to pass through tube 38 intoreceptacle 34 as before and after a predetermined time will cause areenergization of the motor again to close the switch in the manneralready described. It will thus be seen that as long as the centrifugalmechanism is rotating in response to a previous energization at a speedsuflicient to retain lever IS in the position shown by Figs. 1 and 2,the device 25 is retained in an inoperative position. That is, thecircuit of the motor is not closed thereby until the speed of thecentrifugal mechanism falls to such a low value that the switchoperating apparatus can reset itself.

Inasmuch as the flow of fluid into chamber 32, see Fig. 4, is restrictedby the size of the opening of the tube 39, all of the fluid will nothagetime to return to chamber 32 and after the pparatus has reclosed acertain number of times within a predetermined length of time, therewill be an insuflicient amount of fluid in chamber 32 to flll thereceptacle 34. Thus if the abnormal condition on the line persistsindefinitely, the switch will recluse only a predetermined number oftimes after which no further effort will be made by the switch to closethe circuit. Each time the device 25 is moved to the intermediateposition shown by Figs. 2 and 5 the fluid which has not yet returned tochamber 32 remains in chamber 33, the intermediate position therebybeing an inoperative position in which the device is held until thespeed of the centrifugal app ratus has reduced to such a value that themechanism can reset.

We have chosen the particular embodiment described as illustrative ofour invention and it will be apparent that various modifications may bemade without departing from the spirit and scope of our invention whichmodifications we aim to cover by the appended claims.

What we claim as new and desire to secure by Letters Patent of theUnited States is:

1. A reclosing circuit breaker comprising a main switch, a motor drivencentrifugal operating device therefor, a latch controlled collapsibleconnection between said switch and said device, said connection beingconstructed to reset itself 'in non-collapsed condition when the speedof the device decreases to a predetermined minimum, a movably mountedtime delay switch having an operative and an inoperative position forcontrolling said motor and means operative to hold said time delayswitch in its inoperative position when said connection is collapsed andto move the same into its operative position in response to theresetting of said connection.

2. A reclosing circuit breaker comprising a main switch, a motor drivencentrifugal operating device therefor, a latch controlled collapsibleconnection between said switch and said device, said connection beingconstructed to reset itself in non-collapsed condition when the speed ofthe device decreases to a predetermined minimum, a movably mountedmercury time delay switch for controlling said motor having an operativeand an inoperative position, and mechanism connecting said time delayswitch with said connection operative to retain the time delay switch inits inoperative position when the main switch is open and saidconnection is collapsed and to move the time delay switch to itsoperative position when 40 the connection subsequently becomes reset.

3. A reclosing circuit breaker comprising a main switch, a motor drivencentrifugal operating device therefor, a latch controlled collapsibleconnection between said switch and said device, said connection beingconstructed to reset itself in non-collapsed condition when the speed ofthe device decreases to a predetermined minimum, a pivotally mountedmercury time delay switch for controlling said motor having an operativeposition, an inverted position and an intermediate inoperative position,means for moving said time delay switch to its operative position whenthe main switch is open and said connection is reset and for moving thesame to its inverted position when the main switch is closed and theconnection is reset and means for retaining the device in itsintermediate position while the switch is open and the connection iscollapsed.

4. A reclosing circuit breaker comprising a main switch, a motor drivencentrifugal operating device therefor, an auxiliary switch forcontrolling said motor, means tending to move said auxiliary switch toclosed circuit position in response to a tripping open of said mainswitch, and means operative to restrain said means if the centrifugaldevice has a speed greater than a predetermined value.

5. A reclosing circuit breaker comprising a main switch, a motor drivencentrifugal operating device therefor, an auxiliary switch forcontrolling said motor, means tending to move said auxiliary switch toclosed circuit position in response to a tripping open of said mainswitch, and means controlled by said centrifugal device for restrainingsaid means until the speed of said device shall have decreased to apredetermined value.

CHARLES H. HILL. ARVID E. ANDERSON.

